Displacement Control Valve of Variable Displacement Inclined Plate-Type Compressor

ABSTRACT

A displacement control valve of a variable displacement inclined plate-type compressor, the displacement control valve controlling the discharge displacement of the compressor by opening and closing a communication path between a discharge chamber and a crank chamber. The displacement control valve has a valve hole formed in the communication path and always communicating with the discharge chamber, a valve body for opening and closing the valve hole, a support hole provided coaxially with the valve hole, a support rod slidably inserted into the support hole and connected to the valve body, an electromagnetic solenoid for driving the valve body, and a pressure sensing chamber for introducing a suction pressure or crank chamber pressure of the compressor into the end section of the support rod which is on the side opposite to the side of the valve body. The displacement control valve can be made smaller than conventional displacement control valves.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a displacement control valve of avariable displacement inclined plate-type compressor, and specifically,relates to a displacement control valve incorporated into a variabledisplacement inclined plate-type compressor which is suitable for use ina refrigeration cycle of an air conditioning system for vehicles.

BACKGROUND ART OF THE INVENTION

Patent Document 1 discloses a displacement control valve of a variabledisplacement inclined plate-type compressor for controlling a dischargedisplacement of the compressor by opening and closing a valve holeformed in a communication path between a discharge chamber and a crankchamber of the compressor, the displacement control valve including thevalve hole always communicating with the crank chamber, a valve body foropening and closing the valve hole, and an electromagnetic solenoid fordriving the valve body. In the displacement control valve disclosed inthis Patent Document 1, a force applied to the valve body at the time ofvalve closing is represented by the following equation (1). Thefollowing equation (1) stands on the premise that the crank chamberpressure decreases down to a pressure almost equal to a suction pressureat the time of valve closing.F=f(1)−fs+(Pd−Ps)Sv+fs′  (1)Where,

-   f(1): electromagnetic force of the electromagnetic solenoid-   fs: urging force of a releasing spring of the electromagnetic    solenoid-   Pd: discharge pressure-   Ps: suction pressure-   Sv: cross-sectional area of the valve hole-   fs′: urging force of a spring for pressing the valve body-   Patent Document 1: JP-A-7-286581

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

However, there are the following problems in the displacement controlvalve disclosed in the above-described Patent Document 1.

When the valve body is closed, because a pressure difference between thedischarge pressure Pd and the suction pressure Ps urges the valve bodyin a direction of valve closing, in order to forcibly open the valvebody by degaussing of the electromagnetic solenoid, it is necessary toset the urging force fs of the releasing spring of the electromagneticsolenoid at a value of (Pd−Ps)Sv+fs′ or more. In order to forcibly openthe valve body in a region with a high discharge pressure Pd, it isnecessary to use a releasing spring with a great spring force fs, and itis necessary to generate a great electromagnetic force for exciting theelectromagnetic solenoid and attracting a movable core against thespring force Fs of the releasing spring, and whereby, theelectromagnetic solenoid becomes large.

Paying attention to the above-described problems, an object of thepresent invention is to provide a displacement control valve of avariable displacement inclined plate-type compressor, which can be madesmaller than that disclosed in Patent Document 1.

Means for Solving the Problems

To achieve the above-described object, a displacement control valve of avariable displacement inclined plate-type compressor according to thepresent invention is provided as a displacement control valve forcontrolling a discharge displacement of the compressor by opening andclosing a communication path between a discharge chamber and a crankchamber of the compressor. The displacement control valve comprises avalve hole formed in the communication path and always communicatingwith the discharge chamber, a valve body for opening and closing thevalve hole, a support hole provided coaxially with the valve hole, asupport rod slidably inserted into the support hole and connected to thevalve body, an electromagnetic solenoid for driving the valve body, anda pressure sensing chamber for introducing a suction pressure or crankchamber pressure of the compressor into an end section of the supportrod which is on a side opposite to a side of the valve body.

In this displacement control valve, a force F applied to the valve bodyat the time of valve closing is represented by the following equation(2). The following equation (2) stands on the premise that the crankchamber pressure decreases down to a pressure almost equal to a suctionpressure at the time of valve closing.F=f(1)−fs±(Pd−Ps)×(Sv−Sr)   (2)Where,

-   f(1): electromagnetic force of the electromagnetic solenoid-   fs: urging force of a releasing spring of the electromagnetic    solenoid-   Pd: discharge pressure-   Ps: suction pressure-   Sv: cross-sectional area of the valve hole-   Sr: cross-sectional area of the support rod

Where, the “±” in the equation (2) is “−” when Sv>Sr, and “+” whenSv<Sr.

In such a displacement control valve according to the present invention,in order to forcibly open the valve body by degaussing of theelectromagnetic solenoid, the force fs of the releasing spring of theelectromagnetic solenoid may be set at (Pd−Ps)×(Sv−Sr) or more. Thisspring force (Pd−Ps)×(Sv−Sr) is clearly smaller than the spring force(Pd−Ps)Sv+fs′ required for the displacement control valve in theaforementioned Patent Document 1. Therefore, the displacement controlvalve according to the present invention can be made smaller than thedisplacement control valve of Patent Document 1.

In the displacement control valve according to the present invention, itis preferred that a cross-sectional area of the valve hole is set nearlyequal to but greater than a cross-sectional area of the support rod.Thus, if the cross-sectional area of the valve hole is set nearly equalto but greater than the cross-sectional area of the support rod, thedischarge pressure operates in a valve opening direction at the time ofvalve closing. Therefore, by degaussing of the electromagnetic solenoid,the valve body is surely opened by the urging force of the releasingspring.

Further, in the displacement control valve according to the presentinvention, it is preferred that a contact part of the valve hole withthe valve body is made of a hard material. By making the contact part ofthe valve hole with the valve body, that is, the valve seat, from a hardmaterial, abrasion of the valve seat due to repeated contact of thevalve body may be suppressed.

Further, in the displacement control valve according to the presentinvention, it is preferred that the valve hole and the support hole areintegrally formed by a hard material. By forming the valve hole and thesupport hole from a hard material, abrasion of the valve seat due torepeated contact of the valve body and abrasion of the support hole dueto repeated slide of the support rod may be suppressed. By forming thevalve hole and the support hole integrally, the structure of thedisplacement control valve may be simplified as compared with a casewhere both are formed separately.

Moreover, in the displacement control valve according to the presentinvention, it is preferred that a valve housing formed with the valvehole and the support hole and containing the valve body and the supportrod is made from a resin or an aluminum alloy. Thus, by making the valvehousing from a resin or an aluminum alloy, the weight of thedisplacement control valve may be reduced.

Effect According to the Invention

In the displacement control valve of a variable displacement inclinedplate-type compressor according to the present invention, the force ofthe releasing spring of the electromagnetic solenoid required forforcibly opening the valve body can be made smaller than the force ofthe releasing spring required in the displacement control valve ofPatent Document 1. Therefore, the displacement control valve accordingto the present invention can be made smaller than the displacementcontrol valve of Patent Document 1.

BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 is a vertical sectional view of a variable displacement inclinedplate-type compressor having a displacement control valve according to afirst embodiment of the present invention.

FIGS. 2A and 2B are vertical sectional views of the displacement controlvalve according to the first embodiment, FIG. 2A shows a valve closingcondition, and FIG. 2B shows a valve opening condition.

FIG. 3A is a vertical sectional view of a displacement control valveaccording to a modification of the first embodiment, and FIG. 3B is anenlarged, partial, vertical sectional view thereof.

FIG. 4A is a vertical sectional view of a displacement control valveaccording to another modification of the first embodiment, and FIG. 4Bis an enlarged, partial, vertical sectional view thereof.

FIGS. 5A and 5B are vertical sectional views of a displacement controlvalve according to a second embodiment of the present invention, FIG. 5Ashows a valve closing condition, and FIG. 5B shows a valve openingcondition.

EXPLANATION OF SYMBOLS

-   1: variable displacement inclined plate-type compressor-   2, 3: displacement control valve-   17: crank chamber-   21: suction chamber-   22: discharge chamber-   26: concave portion-   100,200: valve part-   101,201: valve housing-   102, 203: pressure sensing chamber-   103, 202: valve chamber-   105, 206: support hole-   106, 205: valve hole-   109, 209: valve body-   111, 211: support rod-   120, 220: electromagnetic solenoid

THE BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, desirable embodiments of a displacement control valve of avariable displacement inclined plate-type compressor according to thepresent invention will be explained referring to figures.

First Embodiment

FIGS. 1 and 2 depict a variable displacement inclined plate-typecompressor having a displacement control valve according to a firstembodiment of the present invention. As depicted in FIG. 1, a variabledisplacement inclined plate-type compressor 1 has a main shaft 10, arotor 11 fixed to main shaft 10, and an inclined plate 12 supported bymain shaft 10 at a condition capable of changing its inclination angle.Inclined plate 12 is connected to rotor 11 via a link mechanism 13allowing the change of the inclination angle of inclined plate 12, androtates synchronously with rotor 11 and main shaft 10. Piston 15 isengaged with inclined plate 12 via a pair of shoes 14 sliding on theperiphery of inclined plate 12. Piston 15 is inserted into a cylinderbore 16 a formed in a cylinder block 16. A plurality of pistons 15 aredisposed around main shaft 10 at an interval with each other in thecircumferential direction.

A crank chamber 17 containing main shaft 10, rotor 11 and inclined plate12 is formed by cylinder block 16 and front housing 18. Main shaft 10extends to outside through front housing 18. A shaft seal member 19 isdisposed for sealing the through portion of main shaft 10 in fronthousing 18. A pulley 20 is fixed at a tip portion of main shaft 10. In acase where variable displacement inclined plate-type compressor 1 is acompressor used for a refrigeration cycle of an air conditioning systemfor vehicles, pulley 20 is connected, for example, to an engine (notshown) via a belt (not shown).

A cylinder head 23 forming a suction chamber 21 and a discharge chamber22 is disposed at a position on a side of cylinder block 16 opposite tothe side of front housing 18. Suction chamber 21 is connected to anevaporator (not shown), which is provided in an external circuit, forexample, a refrigeration cycle of an air conditioning system forvehicles, via a suction port (not shown). Discharge chamber 22 isconnected to a condenser (not shown), which is provided in an externalcircuit, for example, a refrigeration cycle of an air conditioningsystem for vehicles, via a discharge port (not shown).

A valve plate 24 formed with suction hole 21 a and discharge hole 22 acommunicating with cylinder bore 16 a is provided between cylinder block16 and cylinder head 23. A discharge valve and a suction valve (notshown) are attached to the valve plate 24. Crank chamber 17 and suctionchamber 21 are communicated with each other via an orifice hole 24 aformed on valve plate 24.

Front housing 18, cylinder block 16, valve plate 24 and cylinder head 23are integrally fastened by a plurality of through bolts 25 disposed atintervals along the circumference with a center of main shaft 10.

A displacement control valve 2 for controlling the dischargedisplacement of variable displacement inclined plate-type compressor 1is fitted into and fixed in a concave portion 26 which is formed incylinder head 23 at a position adjacent to discharge chamber 22. Asshown in FIGS. 1 and 2, displacement control valve 2 has a valve part100 and an electromagnetic solenoid 120 connected to valve part 100.

Valve part 100 has a cylindrical valve housing 101. Three closed spaces27 a, 27 b and 27 c are defined around valve housing 101 by two O-rings101 a and 101 b tightly fitted onto the periphery of valve housing 101and one O-ring 120 a tightly fitted onto the periphery of the case ofelectromagnetic solenoid 120.

In valve housing 101, a lateral partition wall 104 is formed fordividing the inside space of valve housing 101 into a pressure sensingchamber 102 on one end side and a valve chamber 103 on the other endside. On lateral partition wall 104, a support hole 105 communicatingwith pressure sensing chamber 102 and a valve hole 106 communicatingwith valve chamber 103 are formed. Support hole 105 and valve hole 106are disposed on the same axis and communicated with each other. Acommunication hole 107 extending in the radial direction through lateralpartition wall 104 is formed in lateral partition wall 104 passingthrough the communicating portion between support hole 105 and valvehole 106.

Pressure sensing chamber 102 communicates with suction chamber 21 viaclosed space 27 a and a communication path 23 a formed in cylinder head23. Communication hole 107 always communicates with discharge chamber 22via closed space 27 b and a communication path 23 b formed in cylinderhead 23. Valve hole 106 communicating with communication hole 107 alwayscommunicates with discharge chamber 22. Valve chamber 103 communicateswith crank chamber 17 via a communication hole 108 formed in valvehousing 101, closed space 27 c, a communication path 23 c formed incylinder head 23 and communication path 16 b formed in cylinder block16.

A valve body 109 for opening and closing valve hole 106 is disposed invalve chamber 103. A small-diameter rod 110 extending from valve body109 is inserted into valve hole 106 at a movable condition with a gap. Asupport rod 111 integrally formed with the end portion of small-diameterrod 110 is slidably inserted into support hole 105. Valve part 100 isformed by a series of structures from valve housing 101 to support rod111.

Electromagnetic solenoid 120 has a case 121. The end portion of valvechamber 103 side of valve housing 101 is press fitted into one end ofcase 121. As aforementioned, O-ring 120 a for forming closed space 27 cis fitted onto the periphery of the one end portion of case 121.

Electromagnetic solenoid 120 has a fixed core 122 disposed in case 121,a movable core 123 disposed facing its one end to one end of fixed core122, a releasing spring 124 for urging movable core 123 in a directionapart from the fixed core, an electromagnetic coil 125 surrounding fixedcore 122 and movable core 123, and a rod 126 extending from movable core123 through fixed core 122 at a condition capable of being floated. Thisrod 126 is formed integrally with valve body 109. The rod insertion holeformed in fixed core 122 and a space for containing movable core 123 arecommunicated with valve chamber 103, and is in a condition of the samepressure as that in valve chamber 103.

Next, the operation of displacement control valve 2 will be explained.

As shown in FIG. 2A, when electromagnetic coil 125 is excited, movablecore 123 is moved toward fixed core 122 against the urging force ofreleasing spring 124, and valve body 109 closes valve hole 106. By thisclosing, the communication path between discharge chamber 22 and crankchamber 17, which is formed by communication path 23 b, closed space 27b, communication hole 107, valve hole 106, valve chamber 103,communication hole 108, closed space 27 c, communication path 23 c andcommunication path 16 b, is closed. Therefore, the high-pressurerefrigerant gas in discharge chamber 22 is not supplied into crankchamber 17. Since orifice path 24 a has an area enough to exhaustblow-by gas, which leaks from cylinder bore 16 a to crank chamber 17when piston 15 compresses refrigerant gas in cylinder bore 16 a, intosuction chamber 21, the crank chamber pressure gradually decreases. Whenthe crank chamber pressure decreases, the inclination angle of theinclined plate increases, and the discharge displacement of variabledisplacement inclined plate-type compressor 1 increases.

When electromagnetic coil 125 is degaussed, as shown in FIG. 2B, movablecore 123 moves in a direction apart from fixed core 122 by the urgingforce of releasing spring 124, and valve body 109 opens valve hole 106.By this opening, the high-pressure refrigerant gas in discharge chamber22 is supplied into crank chamber 17 through the communication pathformed by communication path 23 b, closed space 27 b, communication hole107, valve hole 106, valve chamber 103, communication hole 108, closedspace 27 c, communication path 23 c and communication path 16 b. By thissupply of the high-pressure refrigerant gas, the crank chamber pressureelevates, the inclination angle of the inclined plate decreases, and thedischarge displacement of variable displacement inclined plate-typecompressor 1 decreases.

Thus, the discharge displacement of variable displacement inclinedplate-type compressor 1 is controlled to be changed by the excitationand the degaussing of electromagnetic coil 125.

In displacement control valve 2, a force F applied to valve body 109 atthe time of valve closing is represented by the following equation (2).The following equation (2) stands on the premise that the pressure incrank chamber 17 decreases down to a pressure almost equal to a suctionpressure at the time of valve closing and the pressure in valve chamber103 is applied to the portion around movable core 123.F=f(1)−fs±(Pd−Ps)×(Sv−Sr)   (2)Where,

-   f(1): electromagnetic force of the electromagnetic solenoid-   fs: urging force of the releasing spring of the electromagnetic    solenoid-   Pd: discharge pressure-   Ps: suction pressure-   Sv: cross-sectional area of the valve hole-   Sr: cross-sectional area of the support rod

Where, in the equation (2), the “±” becomes “−” when Sv>Sr, and the “±”becomes “+” when Sv<Sr.

In such a displacement control valve 2, in order to forcibly open valvebody 109 by degaussing of electromagnetic solenoid 120, the force fs ofreleasing spring 124 of the electromagnetic solenoid may be set at(Pd−Ps)×(Sv−Sr) or more. This spring force (Pd−Ps)×(Sv−Sr) is clearlysmaller than the spring force (Pd−Ps)Sv+fs′ required for thedisplacement control valve in the aforementioned Patent Document 1.Therefore, by using a small and weak releasing spring 124, displacementcontrol valve 2 can be made smaller than the displacement control valveof Patent Document 1.

Where, pressure sensing chamber 102 may be communicated with crankchamber 17 instead of suction chamber 21.

In the above-described displacement control valve 2, it is preferredthat the cross-sectional area Sv of the valve hole is set nearly equalto but greater than the cross-sectional area Sr of the support rod. Bysetting the cross-sectional area Sv of the valve hole nearly equal tobut greater than the cross-sectional area Sr of the support rod, thedischarge pressure Pd operates in a valve opening direction at the timeof valve closing. Therefore, by degaussing of the electromagneticsolenoid 120, valve body 109 is surely opened by the urging force ofreleasing spring 124.

As shown in a modification depicted in FIG. 3, in the above-describeddisplacement control valve 2, a structure may be employed wherein a ringmember 112 made of a stainless-group material as a hard material ispress fitted into lateral partition wall 104, and a contact part ofvalve hole 106 with valve body 109 is formed by the ring member 112. Byforming the contact part of valve hole 106 with valve body 109, that is,the valve seat, from the stainless-group material which is a hardmaterial, abrasion of the valve seat due to repeated contact of valvebody 109 may be suppressed.

Further, as shown in another modification depicted in FIG. 4, astructure may be employed wherein a ring member 113 of a stainless-groupmaterial, formed on its wall with a through hole 113 a communicationwith communication hole 107, is press fitted into lateral partition wall104, and valve hole 106 and support hole 105 are integrally formed. Byforming valve hole 106 and support hole 105 from the stainless-groupmaterial which is a hard material, abrasion of the valve seat due torepeated contact of valve body 109 and abrasion of support hole 105 dueto repeated slide of support rod 111 may be suppressed. By integrallyforming valve hole 106 and support hole 105 by ring member 113, thestructure of displacement control valve 2 may be simplified as comparedwith a case where both are formed separately.

Moreover, valve housing 101 may be made from a resin or an aluminumalloy. By making valve housing 101 from a resin or an aluminum alloy,the weight of displacement control valve 2 may be reduced.

Second Embodiment

FIG. 5 shows a displacement control valve of a variable displacementinclined plate-type compressor according to a second embodiment of thepresent invention. As shown in FIG. 5, a displacement control valve 3comprises a valve part 200 and an electromagnetic solenoid 220 connectedto valve part 200.

Valve part 200 has a cylindrical valve housing 201. Three closed spaces27 d, 27 e and 27 f are defined around valve housing 201 by two O-rings201 a and 201 b tightly fitted onto the periphery of valve housing 201and one O-ring 220 a tightly fitted onto the periphery of the case ofelectromagnetic solenoid 220.

In valve housing 201, a lateral partition wall 204 is formed fordividing the inside space of valve housing 201 into a valve chamber 202on one end side and a pressure sensing chamber 203 on the other endside. On lateral partition wall 204, a valve hole 205 communicating withvalve chamber 202 and a support hole 206 communicating with pressuresensing chamber 203 are formed. Valve hole 205 and support hole 206 aredisposed on the same axis and communicated with each other. Acommunication hole 207 extending in the radial direction through lateralpartition wall 204 is formed in lateral partition wall 204 passingthrough the communicating portion between valve hole 205 and supporthole 206.

Pressure sensing chamber 203 communicates with suction chamber 21 orcrank chamber 17 via a communication hole formed in valve housing 201,closed space 27 d and a communication path (not shown) formed incylinder head 23. Communication hole 207 communicates with dischargechamber 22 via closed space 27 e and communication path 23 b formed incylinder head 23. Valve hole 205 communicating with communication hole207 always communicates with discharge chamber 22. Valve chamber 202communicates with crank chamber 17 via closed space 27 f, acommunication path (not shown) formed in cylinder head 23, and acommunication path (not shown) formed in cylinder block 16.

A valve body 209 for opening and closing valve hole 205 is disposed invalve chamber 202. A small-diameter rod 210 extending from valve body209 is inserted into valve hole 205 at a movable condition with a gap. Asupport rod 211 integrally formed with the end portion of small-diameterrod 210 is slidably inserted into support hole 206. Valve part 200 isformed by a series of structures from valve housing 201 to support rod211.

Electromagnetic solenoid 220 has a case 221. The end portion of pressuresensing chamber 203 side of valve housing 201 is press fitted into oneend of case 221. As aforementioned, O-ring 220 a for forming closedspace 27 d is fitted onto the periphery of the one end portion of case221.

Electromagnetic solenoid 220 has a fixed core 222 disposed in case 221,a movable core 223 disposed facing its one end to one end of fixed core222, a releasing spring 224 for urging movable core 223 in a directionapart from the fixed core, an electromagnetic coil 225 surrounding fixedcore 222 and movable core 223, and a rod 226 extending from movable core223. This rod 226 is formed integrally with support rod 211. The spaceforming the end portion of support rod 211 at the side apart from valvebody 206 via rod 226 and containing movable core 223 is communicatedwith pressure sensing chamber 203. Therefore, the pressure in pressuresensing chamber 203, namely, the suction pressure or the crank chamberpressure is applied to movable core 223.

In displacement control valve 3, a force F applied to valve body 209 atthe time of valve closing is same as the force F applied to valve body109 at the time of valve closing in displacement control valve 2 of thefirst embodiment. Therefore, by using a small and weak releasing spring224, displacement control valve 3 can be made smaller than thedisplacement control valve of the aforementioned Patent Document 1.

INDUSTRIAL APPLICATIONS OF THE INVENTION

The present invention can be applied broadly for displacement controlvalves of variable displacement inclined plate-type compressors.

1. A displacement control valve of a variable displacement inclinedplate-type compressor for controlling a discharge displacement of saidcompressor by opening and closing a communication path between adischarge chamber and a crank chamber of said compressor, saiddisplacement control valve comprising: a valve hole formed in saidcommunication path and communicating with said discharge chamber; avalve body for opening and closing said valve hole; a support holeprovided coaxially with said valve hole; a support rod slidably insertedinto said support hole and connected to said valve body; anelectromagnetic solenoid for driving said valve body; and a pressuresensing chamber for introducing a suction pressure or crank chamberpressure of said compressor into an end section of said support rodwhich is on a side opposite to a side of said valve body.
 2. Thedisplacement control valve of a variable displacement inclinedplate-type compressor according to claim 1, wherein a cross-sectionalarea of said valve hole is about equal to but greater than across-sectional area of said support rod.
 3. The displacement controlvalve of a variable displacement inclined plate-type compressoraccording to claim 1, wherein a contact part of said valve hole withsaid valve body is made of a hard material.
 4. The displacement controlvalve of a variable displacement inclined plate-type compressoraccording to claim 1, wherein said valve hole and said support hole areintegrally formed by a hard material.
 5. The displacement control valveof a variable displacement inclined plate-type compressor according toclaim 1, wherein a valve housing formed with said valve hole and saidsupport hole and containing said valve body and said support rod is madefrom a resin or an aluminum alloy.
 6. The displacement control valve ofa variable displacement inclined plate-type compressor according toclaim 2, wherein a contact part of said valve hole with said valve bodyis made of a hard material.
 7. The displacement control valve of avariable displacement inclined plate-type compressor according to claim2, wherein said valve hole and said support hole are integrally formedby a hard material.
 8. The displacement control valve of a variabledisplacement inclined plate-type compressor according to claim 3,wherein said valve hole and said support hole are integrally formed by ahard material.
 9. The displacement control valve of a variabledisplacement inclined plate-type compressor according to claim 6,wherein said valve hole and said support hole are integrally formed by ahard material.
 10. The displacement control valve of a variabledisplacement inclined plate-type compressor according to claim 2,wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 11. The displacement control valve of avariable displacement inclined plate-type compressor according to claim3, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 12. The displacement control valve of avariable displacement inclined plate-type compressor according to claim4, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 13. The displacement control valve of avariable displacement inclined plate-type compressor according to claim6, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 14. The displacement control valve of avariable displacement inclined plate-type compressor according to claim7, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 15. The displacement control valve of avariable displacement inclined plate-type compressor according to claim8, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.
 16. The displacement control valve of avariable displacement inclined plate-type compressor according to claim9, wherein a valve housing formed with said valve hole and said supporthole and containing said valve body and said support rod is made from aresin or an aluminum alloy.